I am interested in upgrading my GPU from a 256MB Nvidia 7600GT to perhaps a AMD 6770.
I have been doing a bit of research on TechArp with their graphics card comparison thing.
Both myself and a family friend have the EXACT same computer, besides the GPU and monitor currently.
He is running an 8800GT and it shows from TechArp that the power usage is about 105W
From TechArp I have seen that the 6770 takes up 108W
I have an Antec 400W SmartPower 2.0 ATX12V V2.0 SP-400 Power Supply, on MSY's website it says for the 6770 Power requirement 450W (one 75W 6-pin PCI Express® connector recommended)

For the people with this graphics card, is it any decent?
Is it possible to get an even better graphics card?
If I can't get the 6770 what other graphics card would be good?

CPU: AMD Athlon 64 3800+ AM2
RAM: 2GB Kingston DDR2-800
HDD: WD 160GB JS 7200RPM 8MB Cache SATA II

I would update your PSU.

750W are about $100-150

Damn, I was looking at doing that later on within the month.
I just wanted this GPU upgrade first, hoping that the current PSU would take it.
The rest of the stuff in this computers about 4-5 years old so I don't see why it wouldn't be able to handle it when the 8800GT only takes 3W less compared to the 6770.

Go for it...

Power rating isn't as important as stable rails so see how you go. Antecs' have quite good voltages across the board so it should be fine.

go for it, 6770 is bit underpowered for my liking, you could get away with running a gtx560 on it which would be far more beneficial

Or try pick up a cheap GTX460

Well I reckon I might go with the 6770 anyway, I thought getting a GTX 560 might be a bit much since it says it takes up about 150W? :S
GTX 460 also takes up the same amount
I personally just want something better than a 7600GT, one that will help me run CoD4 with at least 125 constant and just a bit better on HoN.

Cheers for the help

Power ratings are just general indications and are generally more than what is required to run the GPU.

Ahh yep, I get it now
Thanks.